The invention relates to an air-land-sea vehicle having a box wing configuration. 2. Description of the Prior Art
The NASA Technical Memorandum TM-75872 titled "The High Lift Characteristics in the Case of the V-Wing Concept" written by H. Zimmer and published in Nov. 1980 discloses in FIG. 3 (substantially reproduced herein as prior art FIG. 1) several curves illustrating the ratio of induced drag for various configurations with the same lift and the same wing span. As shown therein, curve d, which is representative of a box wing configuration, has the least ratio of induced drag of any of the wing configurations shown in the figure.
Among other prior art references of some relevance to the present invention are the following:
U.S. Pat. No. 1,058,983 discloses a flying machine having a biplane configuration with movable canards.
U.S. Pat. No. 1,839,194 shows a canard-type airplane having a single main wing.
U.S. Pat. No. 2,553,952 shows a combined land vehicle and airplane having a demountable single main wing and conventional tail surfaces.
U.S. Pat. No. 3,371,886 teaches an aircraft adapted for highway usage having a single main wing and canard wing units.
U.S. Pat. No. 4,627,585 discloses a combination road vehicle and aircraft having a foldable main wing and a pusher-type propeller mounted behind the center of the fuselage to the rear of the main wing.
U.S. Pat. No. 3,960,103 shows a marine skimmer craft (not an airplane) with two main wings and a canard. The main wings are attachable in panels to provide the desired lift.
Other prior art references considered to be of lesser interest with respect to the present invention include the following:
U.S. Pat. No. 1,495,031 describes an airplane having a plurality of wings configured for improved lifting capability.
U.S. Pat. No. 1,523,386 describes an airplane having a biplane wing configuration, and small wings on opposite sides of the engine to provide added lift to the engine during landing.
U.S. Pat. No. 1,705,904 describes an airplane having a multi-wing configuration to increase or reduce the lift in accordance with the load.
U.S. Pat. No. 2,681,773 describes a roadable aircraft with folding wings.
U.S. Pat. No. 3,258,228 describes an aircraft with a separate flight unit and payload unit coupled together.
U.S. Pat. No. 2,147,968 describes an acrobatic aircraft having a wing configuration which provides a minimum gliding ratio as well as buoyancy.
U.S. Pat. No. 3,931,942 is of interest relative to the invention of the present application in its description of an aircraft convertible to an automobile wherein the transition from the ground effect mode to the flight mode is made in flight by simultaneously lowering the tandem of the air foils, lifting the rear wall and altering the angle of attack of the forward air foil.
U.S. Pat. No. 3,954,231 is of some relevance to the invention of the present application in showing a arrangement for lifting, stabilizing, and flight controlling wing surfaces placed near the front of an aircraft with the main lifting wing surfaces placed toward the rear.
U.S. Pat. No. 3,134,560 discloses an aircraft convertible to a ground vehicle with foldable outer wing sections.
French Pat. No. 1,039,983 describes a combination automobile and a detachable airplane with a single wing.